使用VisualStudio,打开NuGet包管理器,搜索NPOI,并添加到当前项目。c++
由于一个Excel文件能够有多个sheet页,因此C#方法最好使用与Excel文档结构相对应的DataSet类,即将DataSet(能够包含多个DataTable)导出为Excel,DataSet中的每一个DataTabel对应一个Excel中的Sheet页。学习
方法解释:此方法将一个Excel文件导入为一个DataSet,Excel中每一个Sheet页都会生成一个DataTable存放在导入的DataSet中,而且每一个DataTable的TableName与每一个Sheet的SheetName一一对应。参数isFirstLineColumnName用来表示Excel文件各表第一行是否为表头。网站
代码以下:spa
/// <summary> /// 读取Execl数据到DataTable(DataSet)中 /// </summary> /// <param name="filePath">指定Execl文件路径</param> /// <param name="isFirstLineColumnName">设置第一行是不是列名</param> /// <returns>返回一个DataTable数据集</returns> public static DataSet ExcelToDataSet(string filePath, bool isFirstLineColumnName) { DataSet dataSet = new DataSet(); int startRow = 0; try { using (FileStream fs = File.OpenRead(filePath)) { IWorkbook workbook = null; // 若是是2007+的Excel版本 if (filePath.IndexOf(".xlsx") > 0) { workbook = new XSSFWorkbook(fs); } // 若是是2003-的Excel版本 else if (filePath.IndexOf(".xls") > 0) { workbook = new HSSFWorkbook(fs); } if (workbook != null) { //循环读取Excel的每一个sheet,每一个sheet页都转换为一个DataTable,并放在DataSet中 for (int p = 0; p < workbook.NumberOfSheets; p++) { ISheet sheet = workbook.GetSheetAt(p); DataTable dataTable = new DataTable(); dataTable.TableName = sheet.SheetName; if (sheet != null) { int rowCount = sheet.LastRowNum;//获取总行数 if (rowCount > 0) { IRow firstRow = sheet.GetRow(0);//获取第一行 int cellCount = firstRow.LastCellNum;//获取总列数 //构建datatable的列 if (isFirstLineColumnName) { startRow = 1;//若是第一行是列名,则从第二行开始读取 for (int i = firstRow.FirstCellNum; i < cellCount; ++i) { ICell cell = firstRow.GetCell(i); if (cell != null) { if (cell.StringCellValue != null) { DataColumn column = new DataColumn(cell.StringCellValue); dataTable.Columns.Add(column); } } } } else { for (int i = firstRow.FirstCellNum; i < cellCount; ++i) { DataColumn column = new DataColumn("column" + (i + 1)); dataTable.Columns.Add(column); } } //填充行 for (int i = startRow; i <= rowCount; ++i) { IRow row = sheet.GetRow(i); if (row == null) continue; DataRow dataRow = dataTable.NewRow(); for (int j = row.FirstCellNum; j < cellCount; ++j) { ICell cell = row.GetCell(j); if (cell == null) { dataRow[j] = ""; } else { //CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,) switch (cell.CellType) { case CellType.Blank: dataRow[j] = ""; break; case CellType.Numeric: short format = cell.CellStyle.DataFormat; //对时间格式(2015.12.五、2015/12/五、2015-12-5等)的处理 if (format == 14 || format == 31 || format == 57 || format == 58) dataRow[j] = cell.DateCellValue; else dataRow[j] = cell.NumericCellValue; break; case CellType.String: dataRow[j] = cell.StringCellValue; break; } } } dataTable.Rows.Add(dataRow); } } } dataSet.Tables.Add(dataTable); } } } return dataSet; } catch (Exception) { return null; } }
代码解释:咱们能够将要导出的DataTable都放入一个DataSet中,将DataSet导出为Excel文件,方法参数OutPath用来传入导出Excel文件的路径,路径能够加Excel的扩展名(.xls或.xlsx),也能够不加,不加默认导出Excel文件扩展名为.xls。 excel
/// <summary>
/// 将DataTable(DataSet)导出到Execl文档 /// </summary>
/// <param name="dataSet">传入一个DataSet</param>
/// <param name="Outpath">导出路径(能够不加扩展名,不加默认为.xls)</param>
/// <returns>返回一个Bool类型的值,表示是否导出成功</returns>
/// True表示导出成功,Flase表示导出失败
public static bool DataTableToExcel(DataSet dataSet, string Outpath) { bool result = false; try { if (dataSet == null || dataSet.Tables == null || dataSet.Tables.Count == 0 || string.IsNullOrEmpty(Outpath)) throw new Exception("输入的DataSet或路径异常"); int sheetIndex = 0; //根据输出路径的扩展名判断workbook的实例类型
IWorkbook workbook = null; string pathExtensionName = Outpath.Trim().Substring(Outpath.Length - 5); if (pathExtensionName.Contains(".xlsx")) { workbook = new XSSFWorkbook(); } else if(pathExtensionName.Contains(".xls")) { workbook = new HSSFWorkbook(); } else { Outpath = Outpath.Trim() + ".xls"; workbook = new HSSFWorkbook(); } //将DataSet导出为Excel
foreach (DataTable dt in dataSet.Tables) { sheetIndex++; if (dt != null && dt.Rows.Count > 0) { ISheet sheet = workbook.CreateSheet(string.IsNullOrEmpty(dt.TableName) ? ("sheet" + sheetIndex) : dt.TableName);//建立一个名称为Sheet0的表
int rowCount = dt.Rows.Count;//行数
int columnCount = dt.Columns.Count;//列数 //设置列头
IRow row = sheet.CreateRow(0);//excel第一行设为列头
for (int c = 0; c < columnCount; c++) { ICell cell = row.CreateCell(c); cell.SetCellValue(dt.Columns[c].ColumnName); } //设置每行每列的单元格,
for (int i = 0; i < rowCount; i++) { row = sheet.CreateRow(i + 1); for (int j = 0; j < columnCount; j++) { ICell cell = row.CreateCell(j);//excel第二行开始写入数据
cell.SetCellValue(dt.Rows[i][j].ToString()); } } } } //向outPath输出数据
using (FileStream fs = File.OpenWrite(Outpath)) { workbook.Write(fs);//向打开的这个xls文件中写入数据
result = true; } return result; } catch (Exception ex) { return false; } } }
将上面两个方法都定义在ExcelHelper类中,使用以下代码使用:code
DataSet set = ExcelHelper.ExcelToDataTable("test.xlsx", true);//Excel导入 bool b = ExcelHelper.DataTableToExcel(set, "test2.xlsx");//导出Excel